To my memory you will spend around $325-$350 to get one set up. Also keep in mind you will also have to have yearly renewal fees in the estimated amount of $325. Then if you do any deals with your LLC you will have to file a tax return for it.
If protection is what you are concerned about then get more insurance coverage.
I had one created by an attorney and one with Legal Zoom. They look about the same and both cost about $300-350 (in Iowa). Some people might say if you have no personal assets what is the LLC protecting? I suppose it depends on your assets and investment goals. I have purchased all but my first property in an LLC.
Organizing an LLC should be fairly easy and cost effective. As an attorney, I have done this before, in several states. Go to your state's secretary of state's office and follow the guide.
If you are partnering with another person, I recommend an LLC, and I also recommend an operating agreement. The OA governs how the relationship will work. Without one, state default rules apply, which you may not want.
Even without a partner, you may find an LLC helpful in terms of tax benefits. However, before I tread in water to far away from my expertise, I defer you to your accountant.
Shaun
It's $50 to register with the state in Iowa but banks have asked me for the Articles of Organization and the Operating Agreement. That is what cost $300, just to be clear.